Power supply apparatus with dynamic scaling feature of switching frequency

Patent metadata

Field	Value
Publication number	US-11469658-B2
Application number	US-202017117037-A
Country	US
Kind code	B2
Filing date	Dec 9, 2020
Priority date	Dec 10, 2019
Publication date	Oct 11, 2022
Grant date	Oct 11, 2022

Abstract

Disclosed is a power supply apparatus including a DC-DC converter implemented as one integrated circuit. A duty of a switching pulse of a DC-DC conversion unit is controlled according to a phase difference between a feedback clock signal and a reference clock signal having a frequency proportional to an output voltage of the DC-DC conversion unit. The duty of the switching pulse may be controlled from an output of a charge pump to be charged and discharged according to the phase difference signal between the feedback clock signal and the reference clock signal.

First claim

What is claimed is:

1. A power supply apparatus comprising:
a reference clock generation unit configured to generate and output a reference clock signal;
a switching pulse generation unit configured to generate and output a switching pulse obtained by changing a duty of the reference clock signal;
a DC-DC conversion unit configured to switch an input power by the switching pulse, convert it into a DC voltage and output the same; and
a voltage-controlled frequency feedback unit configured to generate and output a duty control signal for controlling a duty of the switching pulse generated and output by the switching pulse generation unit according to a phase difference between a feedback clock signal having a frequency proportional to an output voltage of the DC-DC conversion unit and the reference clock signal,
wherein the voltage-controlled frequency feedback unit comprises:
a voltage-controlled oscillation unit configured to oscillate and output the feedback clock signal having a frequency proportional to the output voltage of the DC-DC conversion unit,
a phase difference signal generation unit configured to detect a phase difference between the feedback clock signal and the reference clock signal, and output a phase difference signal; and
a duty control signal generation unit configured to generate and output the duty control signal for controlling the duty of the switching pulse generated and output by the switching pulse generation unit from the phase difference signal,
wherein the phase difference signal generation unit comprises:
a phase difference detection unit configured to detect the phase difference between the feedback clock signal and the reference clock signal; and
a charge pump which is charged and discharged according to a phase difference signal output from the phase difference detection unit, and
wherein the duty control signal generation unit comprises:
a comparator configured to output a difference in signals between the phase difference signal and a band gap reference signal; and
a duty tracking controller configured to receive the difference in signals output from the comparator, subtract or add it from or to the current duty control signal, and output a new duty control signal.

2. The power supply apparatus according to claim 1 , wherein the duty control signal generation unit comprises:
a filter unit configured to settle an output of the charge pump and output a phase difference voltage signal; and
a duty tracking controller configured to generate and output the duty control signal obtained by reflecting a current duty from the phase difference voltage signal.

3. The power supply apparatus according to claim 2 , wherein the switching pulse generation unit comprises:
a multiple duty signal generation unit configured to generate a plurality of switching pulse signals obtained by modulating the reference clock signals so as to have different duties from each other;
a duty selection unit configured to output one signal selected by the duty control signal among the plurality of switching pulse signals.

4. A power supply apparatus comprising:
a multiple reference clock generation unit configured to output one of a plurality of reference clock signals having different frequencies from each other;
a switching pulse generation unit configured to generate and output a switching pulse obtained by changing a duty of the reference clock signal output from the multiple reference clock generation unit;
a DC-DC conversion unit configured to switch an input power by the switching pulse, convert it into a DC power and output the same; and
a voltage-controlled frequency feedback unit configured to generate and output a duty control signal for controlling a duty of the switching pulse generated and output by the switching pulse generation unit according to a phase difference between a feedback clock signal having a frequency proportional to an output voltage of the DC-DC conversion unit and the reference clock signal output by the multiple reference clock generation unit; and
a controller which includes an output voltage setting unit configured to output a reference clock selection signal for selecting a frequency of the reference clock signal to the multiple reference clock generation unit according to an external instruction signal.

5. The power supply apparatus according to claim 4 , wherein the voltage-controlled frequency feedback unit comprises:
a voltage-controlled oscillation unit configured to oscillate and output the feedback clock signal having the frequency proportional to the output voltage of the DC-DC conversion unit,
a phase difference signal generation unit configured to detect the phase difference between the feedback clock signal and the reference clock signal output from the multiple reference clock generation unit, and output a phase difference signal; and
a duty control signal generation unit configured to generate and output the duty control signal for controlling the duty of the switching pulse generated and output by the switching pulse generation unit from the phase difference signal.

6. The power supply apparatus according to claim 5 , wherein the phase difference signal generation unit comprises:
a phase difference detection unit configured to detect the phase difference between the feedback clock signal and the reference clock signal output from the multiple reference clock generation unit; and
a charge pump which is charged and discharged according to the phase difference signal output from the phase difference detection unit.

7. The power supply apparatus according to claim 6 , wherein the duty control signal generation unit comprises:
a comparator configured to output a difference in signals between the phase difference signal and a band gap reference signal; and
a duty tracking controller configured to receive the difference in signals output from the comparator, subtract or add it from or to the current duty control signal, and output a new duty control signal.

8. A power supply apparatus comprising:
a multiple reference clock generation unit configured to output one of a plurality of reference clock signals having different frequencies from each other;
a switching pulse generation unit configured to generate and output a switching pulse obtained by changing a duty of the reference clock signal output from the multiple reference clock generation unit;
a DC-DC conversion unit configured to switch an input power by the switching pulse, convert it into a DC power and output the same; and
a voltage-controlled frequency feedback unit configured to generate and output a duty control signal for controlling a duty of the switching pulse generated and output by the switching pulse generation unit according to a phase difference between a feedback clock signal having a frequency proportional to an output voltage of the DC-DC conversion unit and the reference clock signal output by the multiple reference clock generation unit; and
a controller which includes a reference frequency controller configured to measure input and output parameters of the DC-DC conversion unit, and output a reference clock selection signal for selecting one of the plurality of reference clock signals to the multiple reference clock generation unit.

9. The power supply apparatus according to claim 8 , wherein the controller further comprises:
a switching initialization unit configured to measure an input voltage, an input current, an output voltage, an output current, and at least one output parameter of the DC-DC conversion unit, and determine and output initial values of the reference clock selection signal and the duty control signal of the voltage-controlled frequency feedback unit so as to

Assignees

• Skaichips Co Ltd
• Research & Business Found Sungkyunkwan Univ
• Skaichipsco Ltd

Inventors

• Lee Kang Yoon
• Jo Jong Wan
• Choi Kyung Duk
• Pu Young Gun

Classifications

• H02M1/0003

  Details of control, feedback or regulation circuits · CPC title

• H02M3/156 Primary

  with automatic control of output voltage or current, e.g. switching regulators · CPC title

• H03K5/1565

  the output pulses having a constant duty cycle · CPC title

• H03L7/093

  using special filtering or amplification characteristics in the loop (H03L7/087 - H03L7/091 take precedence) · CPC title

• H02M1/0009

  Devices or circuits for detecting current in a converter · CPC title